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Galactic Defenders: A Journey through the 1980s Pixelated Universe Lab

This JavaScript Front End Web Development lab combines the thematic elements of space a return to the classic, pixelated video games that were a hallmark of the '80s. It's a celebration of the coin-operated arcade machines and the iconic games of that era, drawing us into an experience that recaptures the fun and creativity of 1980s video gaming.
Let's dive into an exciting adventure of creating a Space Defenders game with HTML, JavaScript, and CSS. This will be a throwback to the golden era of 1980s video arcade games.

Part 1: Introduction to Space Defenders

Lecture

Space Defenders is a classic arcade game where the player controls a spaceship and must defend against incoming enemy spaceships. We will create this game using HTML5 Canvas for rendering, JavaScript for game logic, and CSS for styling.
Key Concepts:
HTML5 Canvas: For drawing graphics on a web page.
JavaScript Event Handling: To capture keyboard inputs.
Browser Object Model (BOM): For interaction with the browser.
Questions:
What is the role of HTML5 Canvas in game development?
Answer: It provides a 2D rendering context for drawing graphics.
How can we capture keyboard inputs in JavaScript?
Answer: By using event listeners for keydown events.
Resource References:
⁠
HTML5 Canvas Tutorial
⁠
⁠
⁠
JavaScript Event Handling
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Coding Exercise 1: Setting up HTML and Canvas

Let's start by creating the HTML structure.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Space Defenders</title>
<link rel="stylesheet" href="styles.css">
</head>
<body>
<canvas id="gameCanvas" width="800" height="600"></canvas>
<script src="game.js"></script>
</body>
</html>

Questions:
What is the purpose of the canvas element?
Answer: It provides a drawing surface for rendering graphics.

Part 2: Styling with CSS

Coding Exercise 2: Adding Basic Styling

We'll add some basic styles to center the canvas.

body {
display: flex;
justify-content: center;
align-items: center;
background-color: black;
height: 100vh;
margin: 0;
}

#gameCanvas {
border: 2px solid white;
}

Part 3: JavaScript and Game Logic

Coding Exercise 3: Drawing the Player's Ship

We'll begin the game development by drawing the player's ship.
game.js

const canvas = document.getElementById('gameCanvas');
const ctx = canvas.getContext('2d');

// Draw player's ship
function drawShip(x, y) {
ctx.fillStyle = 'white';
ctx.beginPath();
ctx.moveTo(x, y);
ctx.lineTo(x - 20, y + 20);
ctx.lineTo(x + 20, y + 20);
ctx.closePath();
ctx.fill();
}

drawShip(400, 550);

Questions:
What does ctx represent in the code?
Answer: It represents the 2D rendering context for the canvas, allowing us to draw shapes, lines, and text.
The above code sets up the game and draws a simple triangle representing the player's ship.
⁠
We have successfully introduced the basics of creating a Space Defenders game, touching on HTML, CSS, and JavaScript essentials.
In the next modules, we will explore further features, including movement controls, shooting mechanics, and enemy behaviors. This will involve introducing more concepts and enhancing the complexity of our code.
Do you want me to proceed with the next modules?
Let’s proceed to find out how to include movement controls, shooting mechanics, and enemy behaviors
Move on to the next exciting parts of our Space Defenders game development.

Part 4: Movement Controls

Lecture

In this part, we'll learn how to add movement controls to the player's ship using the cursor keys.
Key Concepts:
Event Listeners: Capturing keyboard events.
Game Loop: Continuously updating the game state.
Questions:
What is the purpose of a game loop?
Answer: A game loop is a continuous loop that updates the game state and redraws the scene, providing real-time interactivity.

Coding Exercise 4: Adding Movement Controls

We will use the 'keydown' and 'keyup' events to control the movement of the player's ship.
javascriptCopy code
let shipX = 400;
let shipY = 550;
let shipSpeed = 0;

window.addEventListener('keydown', function (event) {
if (event.key === 'ArrowLeft') shipSpeed = -5;
if (event.key === 'ArrowRight') shipSpeed = 5;
});

window.addEventListener('keyup', function (event) {
if (event.key === 'ArrowLeft' || event.key === 'ArrowRight') shipSpeed = 0;
});

function update() {
shipX += shipSpeed;
ctx.clearRect(0, 0, canvas.width, canvas.height);
drawShip(shipX, shipY);
requestAnimationFrame(update);
}

update();

Part 5: Shooting Mechanics

Lecture

We'll learn how to implement shooting mechanics, allowing the player's ship to fire bullets.
Key Concepts:
Object Arrays: Managing bullets.
Collisions: Handling bullet impacts.
Questions:
How can object arrays be used to manage multiple bullets?
Answer: By storing each bullet as an object in an array, we can easily iterate and update their positions and handle interactions.

Coding Exercise 5: Adding Shooting Mechanics

We'll implement shooting by pressing the space bar.

let bullets = [];

window.addEventListener('keydown', function (event) {
if (event.key === ' ') {
bullets.push({ x: shipX, y: shipY - 10, speed: -5 });
}
});

function drawBullets() {
ctx.fillStyle = 'red';
bullets.forEach(bullet => {
ctx.fillRect(bullet.x - 2, bullet.y - 2, 4, 4);
});
}

function updateBullets() {
bullets.forEach(bullet => {
bullet.y += bullet.speed;
});
}

function update() {
// ...
updateBullets();
drawBullets();
// ...
}

update();

Part 6: Enemy Behaviors

Lecture

Finally, we'll introduce enemies, focusing on their behavior, movement patterns, and interactions.
Key Concepts:
AI Patterns: Simple AI for enemy movement.
Collision Detection: Interactions between bullets and enemies.
Questions:
How can we implement simple AI patterns for enemy movement?
Answer: By using functions that dictate movement patterns or behaviors, such as following a path or random movement.

Coding Exercise 6: Adding Enemy Behaviors

Let's add enemies and their movement patterns.
let enemies = [
{ x: 100, y: 100, speed: 1 },
// More enemies
];

function drawEnemies() {
ctx.fillStyle = 'blue';
enemies.forEach(enemy => {
ctx.fillRect(enemy.x - 10, enemy.y - 10, 20, 20);
});
}

function updateEnemies() {
enemies.forEach(enemy => {
enemy.x += enemy.speed;
// Additional behavior
});
}

function update() {
// ...
drawEnemies();
updateEnemies();
// ...
}

update();

⁠
With this, we've covered the essential elements of the Space Defenders game. Further enhancement can be made by adding features like score tracking, levels, and more complex enemy behaviors.
Resource References:
⁠
JavaScript Keydown Event
⁠
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⁠
Game Loop and Animations
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These exercises will provide the students with hands-on experience in game development, engaging them with both the technicalities and the fun aspects of coding.
It's a valuable experience that merges creativity with coding, something that they can take forward in their journey as Full Stack Web Developers.

Next steps: Add features like score tracking, levels, and more complex enemy behaviors.
Let's expand our Space Defenders game with additional features, including score tracking, multiple levels, and more complex enemy behaviors.

Part 7: Score Tracking

Lecture

Keeping score adds competitive elements and a sense of accomplishment to games.
Key Concepts:
Variable Management: Storing the score.
Text Rendering: Displaying the score on the canvas.
Questions:
How can we display text on the canvas?
Answer: We can use the fillText method in the canvas rendering context.

Coding Exercise 7: Adding Score Tracking

We'll add a score that increases when the player hits an enemy.
javascriptCopy code
let score = 0;

function drawScore() {
ctx.fillStyle = 'white';
ctx.font = '20px Arial';
ctx.fillText(`Score: ${score}`, 10, 30);
}

function update() {
// ...
drawScore();
}

// Increment score when an enemy is hit
function hitEnemy(enemyIndex) {
enemies.splice(enemyIndex, 1);
score += 10;
}

Part 8: Levels

Lecture

Adding levels to a game creates progression, making the game more engaging.
Key Concepts:
Level Design: Creating multiple stages or difficulties.
Transition Management: Handling progression between levels.
Questions:
What is level design, and why is it essential?
Answer: Level design involves creating stages or challenges, each with its unique layout and difficulty. It adds depth and progression to the game.

Coding Exercise 8: Adding Levels

We'll implement levels by increasing difficulty as the player progresses.
let level = 1;

function nextLevel() {
level++;
// Increase difficulty
enemies.push({ x: 50 * level, y: 100, speed: 1 * level });
// Additional changes for new level
}

function checkLevelCompletion() {
if (enemies.length === 0) {
nextLevel();
}
}

function update() {
// ...
checkLevelCompletion();
}

Part 9: Complex Enemy Behaviors

Lecture

Enhancing enemy behaviors makes the game more challenging and fun.
Key Concepts:
AI Behaviors: Making enemies move in patterns or react to the player.
Randomization: Introducing variability in enemy actions.
Questions:
How can we make enemies move in patterns?
Answer: By using mathematical functions or predefined paths to dictate their movement.

Coding Exercise 9: Adding Complex Enemy Behaviors

Let's introduce more complex movement patterns for the enemies.
javascriptCopy code
function updateEnemies() {
enemies.forEach(enemy => {
// Example: Sinusoidal movement
enemy.x += Math.sin(enemy.y) * enemy.speed;
enemy.y += enemy.speed;
});
}

Resource References:
⁠
Text Rendering on Canvas
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⁠
Creating Levels in Games
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With these additional features, our Space Defenders game has evolved into a complete and engaging experience. It now includes various levels, a scoring system, and more complex enemy behaviors.
These exercises provide you with a comprehensive understanding of game development in the context of web technologies.
By going through these coding exercises, you will gain valuable insights into how different aspects of a game come together to create a cohesive and fun experience.
This knowledge can be further applied to their future work in Full Stack Web Development, showcasing not just technical skills but also creativity and problem-solving abilities.
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